What is a medicine that serves for many uses, or that cures many diseases. [Obs.] Polychrest salt (Old Med. Chem.), potassium sulphate, specifically obtained by fusing niter with sulphur called?

polychrest — A medicine that serves for many uses, or that cures many diseases. [Obs.] Polychrest salt (Old Med. Chem.), potassium sulphate, specifically obtained by fusing niter with sulphur. (Webster's 1913.)

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